CN110803773A

CN110803773A - Closed and semi-closed water body water quality purification method and system

Info

Publication number: CN110803773A
Application number: CN201911218197.5A
Authority: CN
Inventors: 周铭; 饶雪峰; 张晓磊; 梁思懿
Original assignee: Zhongye Jingcheng Engineering Technology Co Ltd
Current assignee: MCC Capital Engineering and Research Incorporation Ltd; Zhongye Jingcheng Engineering Technology Co Ltd
Priority date: 2019-12-03
Filing date: 2019-12-03
Publication date: 2020-02-18

Abstract

The invention provides a method and a system for purifying water quality of closed and semi-closed water bodies. The method comprises the steps of rainwater pretreatment at the initial stage of the water body to be purified, sediment in-situ remediation, water quality in-situ purification and water ecological remediation, wherein the water ecological remediation is finally implemented. The system comprises an initial rainwater pretreatment unit, a bottom sediment in-situ remediation unit for performing bottom sediment remediation through microorganisms, a water quality in-situ purification unit and a water ecology remediation unit comprising at least one of a submerged plant group, an emergent aquatic plant group and an aquatic animal group; the initial rainwater pretreatment unit comprises a filler layer, plants planted on the upper layer of the filler layer and microorganisms attached to the surface of the filler layer; the water quality in-situ purification unit comprises a device for realizing artificial oxygenation and water body internal circulation and a biological carrier module, and aerobic microorganisms are attached to and grow on the biological carrier; wherein the water ecology restoration unit is constructed last. The method can rapidly purify the water quality of the water body, improve the self-purification capacity of the water body and restore the ecological system of the water body.

Description

Closed and semi-closed water body water quality purification method and system

Technical Field

The invention relates to the field of water quality purification, in particular to a closed and semi-closed water quality purification method and system.

Background

With the rapid development of economy and the continuous improvement of urbanization level, the pollution degree of closed and semi-closed water bodies in cities and towns and rural areas is increasing day by day, the main reasons of the pollution are that certain exogenous pollution exists, for example, the discharge of domestic wastewater and aquaculture wastewater of surrounding villages and towns, and a large amount of pollutants are carried by initial rainwater to directly flow into the water body, so that the water quality of the water body is poor and exceeds the pollutant holding capacity of the water body, the water quality is deteriorated due to long-term accumulation, and on the other hand, the water body is in a closed or semi-closed state, the water body has poor fluidity and is in a dead water state, the water purification capacity is weak, and again, the water body ecosystem is damaged due to the pollution, the water.

The closed and semi-closed water body has poor fluidity, so that the water body is not circulated, the self-cleaning capacity is low, meanwhile, the water body excessively receives sewage, so that a large amount of organic pollutants exceed the standard, the original aerobic microorganisms in the water body carry out aerobic decomposition on organic matters, a large amount of oxygen is consumed, the water body is insufficient in dissolved oxygen to form an anaerobic environment, so that the anaerobic microorganisms propagate in a large amount, the organic pollutants in the water body are fermented, a plurality of smelly substances such as ammonia gas, hydrogen sulfide, mercaptan and the like are generated, the smelly substances escape from the water surface and enter the atmosphere, human olfactory organs are directly stimulated, meanwhile, heavy metals such as iron, manganese and the like in the water are reduced under the anaerobic condition, sulfur in the rainwater forms sulfides, a large amount of black suspended colloidal particles are formed, and the self chromaticity of the water body.

Meanwhile, the long-term pollutant accumulation of the water body leads to thicker bottom sediment, a large amount of pollutants such as oxygen-consuming organic matters, nitrogen and phosphorus and heavy metals are accumulated in the bottom sediment, and various pollutants in the bottom sediment can be released again under certain conditions to float upwards to pollute the water body, so that the concentration of the pollutants in the water body is increased, the water quality is further deteriorated, the bottom sediment is turned upwards through anaerobic fermentation, the bottom sediment is blacked and smelly, and certain endogenous pollution is caused. Internal pollutants are deposited at the bottom, so that the sediment is black and smelly, the nitrogen and the phosphorus exceed the standards, and the long-term existence of the internal pollutants inevitably affects the water quality and the water surface landscape effect.

Because the water body is polluted, the original aquatic organisms in the water body form a complete community to be damaged, submerged plants in the water body cannot carry out photosynthesis to cause death, aquatic animals in the water body cause death of the animals due to heavy pollution, the original self-cleaning capacity of the water body is almost lost, and non-point source pollution and water replenishing pollution load cannot be consumed.

The existing water purification treatment method at home and abroad at present comprises the following steps: the treatment methods of sewage treatment plant treatment, mobile sewage treatment equipment treatment, artificial wetland, artificial aeration and the like are different from the treatment of domestic sewage in terms of pollution problems of closed and semi-closed water bodies, have the characteristics of openness, ecology, landscape and the like, are uncertain in various factors such as water treatment amount, water quality and the like, cannot be suitable for treatment of sewage treatment plants, artificial wetlands and the like, have large investment and high operation cost, are single in artificial aeration, ecological floating islands and the like, cannot achieve the effect of comprehensive treatment, and are difficult to fundamentally solve the current situation problems of closed or semi-closed water body pollution and ecological system destruction.

Disclosure of Invention

The invention aims to provide a water quality purification method for closed and semi-closed water bodies, which can rapidly purify the water quality of the water bodies, improve the self-purification capacity of the water bodies and restore the ecological system of the water bodies.

In order to realize the aim, the invention provides a method for purifying the water quality of closed and semi-closed water bodies, which comprises the steps of carrying out initial rainwater pretreatment, sediment in-situ remediation, water quality in-situ purification and water ecology remediation on the water body to be purified; wherein, the initial rainwater pretreatment, the sediment in-situ remediation and the water quality in-situ purification are all carried out before the water ecological remediation is carried out.

The initial rainwater pretreatment is non-point source pollution control, is an onshore pretreatment unit and is connected with a water body to be purified so as to reduce the pollution degree of rainwater entering the water body to be purified; the in-situ remediation of the sediment is used for purifying the sediment of the water body to be purified and is usually carried out at the bottom of the water body to be purified; the water quality in-situ purification is used for purifying the water quality of the water body to be purified, and the water ecological restoration is used for improving the self-purification capacity of the water body.

In the above water quality purification method, it is preferable that the initial rainwater treatment is started at a time not later than the time at which the in-situ sediment remediation and the in-situ water quality purification are started. More preferably, the implementation sequence of initial rainwater pretreatment, sediment in-situ remediation, water quality in-situ purification and water ecological remediation sequentially comprises: the method comprises the following steps of firstly, implementing rain pretreatment in an initial stage, then synchronously implementing water quality in-situ purification and sediment in-situ remediation, and finally implementing water ecological remediation; or firstly, synchronously implementing initial rainwater pretreatment and water quality in-situ purification, then implementing bottom sediment in-situ remediation, and finally implementing water ecological remediation; or firstly synchronously implementing initial rainwater pretreatment and sediment in-situ remediation, then implementing water quality in-situ purification, and finally implementing water ecological remediation.

In the above water quality purification method, preferably, the initial rainwater pretreatment is to perform filler filtration, plant purification and microbial purification on rainwater entering a water body to be purified in advance by using an initial rainwater pretreatment unit, wherein the initial rainwater pretreatment unit is constructed around the shore of the water body to be treated, the initial rainwater pretreatment unit is communicated with the water body to be purified, and rainwater subjected to initial rainwater pretreatment can enter the water body; more preferably, the initial rainwater pretreatment unit comprises plants, a planting soil layer, a filler layer and microorganisms, wherein the filler layer is arranged at the lower part of the planting soil layer, the plants are planted in the planting soil layer above the filler layer, and the microorganisms are attached to the root systems of the plants, soil particles of the planting soil layer and/or the filler surface of the filler layer and comprise at least one of facultative bacteria, anaerobic bacteria and aerobic bacteria. The material filling layer in the initial rainwater pretreatment unit can be at least one of gravel, limestone, coal cinder, zeolite and the like; when a plurality of packing layers are selected, the layered laying mode can be selected, and the grain diameter gradually decreases from bottom to top. The plant can be at least one of herba Bulleyani, Miscanthus floridulus, herba Imperatae, radix Euphorbiae Fischerianae, herba Kadsurae Longipedunculatae, and herba Carpesii Cernui; when multiple plants are selected for planting, landscape effects can be comprehensively considered. When the plants are planted in the planting soil layer, the plants root and grow in the planting soil layer, the water quality purification effect is improved, and meanwhile, the surrounding landscape environment is improved.

In the above water purification method, preferably, the in-situ remediation of the sediment is performed by means of microorganism remediation, wherein the microorganism is a heterotrophic microorganism; more preferably, the microorganism includes at least one of EM bacteria, photosynthetic bacteria, Bacillus subtilis, nitrifying bacteria, denitrifying bacteria, yeast, lactic acid bacteria, and the like. The adoption of the heterotrophic microorganism for the in-situ remediation of the sediment helps to recover a beneficial microorganism system at the bottom of the water body to be purified, and the microorganism activates the sediment at the bottom of the water body to be purified, decomposes pollutants in the sediment and repairs the sediment of the water body. In a specific embodiment, a microbial agent containing a large amount of heterotrophic microorganisms is put into the water to be purified, the carrier microorganisms are put into the water, the microorganisms are continuously released at the bottom of a river or a lake, and the microorganisms restore the bottom sludge of the water to be purified.

In the above water purification method, preferably, the area for performing the in-situ remediation of the bottom mud accounts for 80 to 100 percent of the total area of the water body to be purified.

In the water quality purification method, preferably, the water quality in-situ purification adopts a mode of combining artificial oxygenation, water body internal circulation and a biological carrier module to promote water quality purification; improving the dissolved oxygen environment of the water body to be purified and improving the fluidity of the water body. Wherein, the artificial oxygenation and the internal circulation of the water body preferably adopt an intermittent operation mode, more preferably 5-8h is taken as an operation period, and the interval time is 1-3 h; the bio-carrier module preferably comprises at least one of fibrous, strip-like and sheet-like packing, and the like. Adopt artifical oxygenation, water internal circulation's mode, improve water dissolved oxygen environment, improve water mobility, artifical oxygenation and water internal circulation provide favorable growing environment for the operation of biological carrier module, make aerobic microorganism adhere to the growth on biological carrier and form the microbial film of water purification, a large amount of microorganisms pass through metabolism, degrade the pollutant in the aquatic, realize the purification of quality of water gradually. The artificial oxygenation and the internal circulation of the water body are preferably carried out by at least one of submersible aeration plug flow equipment, surface aeration equipment, fountain aeration equipment, pipeline aeration disturbance equipment and the like, so that the internal circulation of the water body is realized, and the artificial oxygenation is realized at the same time, and the artificial oxygenation and internal circulation of the water body are integrated. When the artificial oxygenation and the internal circulation of the water body adopt an intermittent operation mode, on one hand, energy is saved, on the other hand, the aerobic and anoxic alternate operation is realized, the characteristics of microorganisms can be fully utilized, and pollutants in the water body can be better degraded, so that the water quality purification effect is improved; in conclusion, compared with long-time aeration, the method has higher purification efficiency and is more energy-saving. The arrangement of the bio-carrier modules can be selected according to actual conditions, such as uniform arrangement, and multiple arrangement in places with heavy local pollution.

In the above water quality purification method, preferably, the area of the artificial oxygenation and the action area of the internal circulation of the water body in the water quality in-situ purification implementation is 100% of the total area of the water body to be purified.

In the above water quality purification method, preferably, the coverage area of the bio-carrier module in the water quality in-situ purification implementation accounts for 10% -40% of the total area of the water body to be purified. The arrangement of the biological carrier module, the artificial oxygenation and the water body internal circulation equipment can fully consider the implementation of water ecological restoration, reduce the shielding of illumination as far as possible and ensure that the photosynthesis can be carried out on the plants needing photosynthesis during the water ecological restoration. The inventor finds that the coverage area of the biological carrier module accounts for 10% -40% of the total area of the water body to be purified in the water quality in-situ purification implementation, the area for implementing water ecological restoration accounts for 40% -60% of the total area of the water body to be purified, and the cooperation of the two modules is more favorable for achieving a better water body purification effect.

In the above water quality purification method, preferably, the water ecological restoration uses at least one of submerged plants, emergent aquatic plants and aquatic animals to restore the self-purification capacity of the water body, and more preferably, the submerged plant cultivation adopts a unit block type or strip type cultivation manner. Wherein the submerged plant preferably comprises at least one of herba Swertiae Dilutae, hydrilla verticillata, Foliumet spicata, Goldfish algae and curly pondweed; more preferably, 50-350 plants are planted per square meter; when multiple types of combined planting are adopted, planting can be performed according to region division. The emergent aquatic plant preferably comprises at least one of flos Nelumbinis, rhizoma Typhae, herba Alii Fistulosi, rhizoma Phragmitis, rhizoma Acori Calami, Ecliptae herba and herba Lydrobii; more preferably, 10-20 plants are planted per square meter; when various types of combined planting are adopted, the landscape effect can be comprehensively considered, and the partitioned and layered planting can be adopted; the emergent aquatic plant planting area is preferably a shallow water area close to the shoreside (the distance between the emergent aquatic plant planting area and the shoreside is not more than 5m, and the water depth of the emergent aquatic plant planting area is not more than 0.5 m). The aquatic animals preferably include surface, middle and bottom aquatic animals, such as surface, middle, bottom fishes and benthonic animals; more preferably, the surface layer and middle layer aquatic animals are selected from aquatic animals feeding on at least one of zooplankton, phytoplankton, humus and bacteria, and the bottom layer aquatic animals are selected from aquatic animals feeding on humus. When the submerged plant is planted and adopts the unit block type or strip type planting mode, on the one hand, the submerged plant can be uniformly distributed in the water body to play a purifying role, on the other hand, a space is reserved for the growth of the submerged plant in the later stage, on the other hand, the planting quantity of the submerged plant can be reduced to a certain extent, and the quantity of the submerged plant is increased by the growth and the propagation of the submerged plant in the later stage.

The invention also provides a closed and semi-closed water quality purification system, wherein the system comprises: the system comprises an initial rainwater pretreatment unit, a sediment in-situ remediation unit, a water quality in-situ purification unit and a water ecological remediation unit; wherein the content of the first and second substances,

the initial rainwater pretreatment unit is arranged on the coastwise of the water body to be purified and is communicated with the water body to be purified, and rainwater treated by the initial rainwater pretreatment unit can enter the water body to be purified; the initial rainwater pretreatment unit comprises plants, a planting soil layer, a filler layer and microorganisms, wherein the filler layer is arranged at the lower part of the planting soil layer, the plants are planted in the planting soil layer above the filler layer, and the microorganisms are attached to the root systems of the plants, soil particles in the planting soil layer and/or the filler surface of the filler layer;

the bottom sediment in-situ remediation unit is used for performing bottom sediment remediation on the water body to be purified through microorganisms;

the water quality in-situ purification unit comprises a device for realizing artificial oxygenation and internal circulation of the water body to be purified and a biological carrier module, and aerobic microorganisms are attached to and grow on the biological carrier; the device for realizing artificial oxygenation of the water body to be purified and internal circulation of the water body provides a favorable growth environment for the operation of the biological carrier module;

the water ecological restoration unit comprises at least one of a submerged plant group, an emergent aquatic plant group and an aquatic animal group;

the initial rainwater pretreatment unit, the sediment in-situ remediation unit and the water quality in-situ purification unit are constructed before the water ecological remediation unit is constructed.

In the closed and semi-closed water quality purification system, preferably, the initial rainwater treatment unit is constructed no later than the bottom sediment in-situ remediation unit and the water quality in-situ purification unit. More preferably, the initial rainwater pretreatment unit, the sediment in-situ remediation unit, the water quality in-situ purification unit and the water ecological remediation unit are sequentially constructed as follows: the method comprises the following steps of firstly constructing an initial rainwater pretreatment unit, then synchronously constructing a water quality in-situ purification unit and a sediment in-situ remediation unit, and finally constructing a water ecology remediation unit; or firstly, synchronously constructing an initial rainwater pretreatment unit and a water quality in-situ purification unit, then constructing a sediment in-situ remediation unit, and finally constructing a water ecology remediation unit; or firstly, synchronously constructing an initial rainwater pretreatment unit and a sediment in-situ remediation unit, then constructing a water quality in-situ purification unit, and finally constructing a water ecology remediation unit.

In the above closed and semi-closed water quality purification system, preferably, the filler layer in the initial rainwater pretreatment unit comprises at least one of gravel, limestone, coal slag, zeolite, and the like; when a plurality of filler matrixes are selected, the filler matrixes are preferably laid in a layered mode, and the particle sizes gradually decrease from bottom to top.

In the above closed and semi-closed water quality purification system, preferably, the plants in the initial rainwater pretreatment unit include at least one of phragmites australis, miscanthus floridulus, stipa capillata, pennisetum purpureum, pennisetum alopecuroides, haemaphystrium japonicum, sedge, and the like; when multiple plants are selected for planting, landscape effects can be comprehensively considered.

In the closed and semi-closed water quality purification system, the microorganisms in the initial rainwater pretreatment unit preferably include at least one of facultative bacteria, anaerobic bacteria, and aerobic bacteria.

In the closed and semi-closed water quality purification system, preferably, the microbes used by the sediment in-situ remediation unit are heterotrophic microbes; more preferably, the microorganism includes at least one of EM bacteria, photosynthetic bacteria, Bacillus subtilis, nitrifying bacteria, denitrifying bacteria, yeast, lactic acid bacteria, and the like.

In the above closed and semi-closed water quality purification system, preferably, the means for realizing artificial oxygenation and internal circulation of the water to be purified comprises at least one of submersible aeration plug flow equipment, surface aeration equipment, fountain aeration equipment, pipeline aeration disturbance equipment and the like.

In the above closed and semi-closed water quality purification system, preferably, the bio-carrier module includes at least one of fibrous, strip-shaped and sheet-shaped fillers.

In the above closed and semi-closed water quality purifying system, preferably, the submerged plant group comprises at least one of eel grass, black alga, watery tail alga, goldfish alga and curly pondweed. More preferably, the submerged plant group has a plant planting density of 50 to 350 plants per square meter; when multiple types of combined planting are adopted, planting can be performed according to region division.

In the above closed and semi-closed water quality purification system, preferably, the emergent aquatic plant group comprises at least one of emergent aquatic plants including lotus, cattail, shallot, reed, calamus, drocalamus latiflorus, and loosestrife. More preferably, the emergent aquatic plant group has a plant planting density of 10-20 plants per square meter; when various types of combined planting are adopted, the landscape effect can be comprehensively considered, and the partitioned and layered planting can be adopted; the emergent aquatic plant planting area is preferably a shallow water area close to the bank.

In the above closed and semi-closed water quality purification system, preferably, the emergent aquatic plant group is disposed in a shallow water region near the shore in the water to be purified.

In the above closed and semi-closed water quality purification system, preferably, the aquatic animal group includes surface, middle and bottom aquatic animals, such as surface, middle, bottom fishes and benthonic animals; more preferably, the surface layer and middle layer aquatic animals are selected from aquatic animals feeding on at least one of zooplankton, phytoplankton, humus and bacteria, and the bottom layer aquatic animals are selected from aquatic animals feeding on humus.

In the above closed and semi-closed water quality purification system, preferably, the active area of the sediment in-situ remediation unit is 80-100% of the total area of the water to be purified.

In the above closed and semi-closed water quality purification system, preferably, the active area of the artificial oxygenation and internal circulation of the water in the water quality in-situ purification unit is 100% of the total area of the water to be purified.

In the above closed and semi-closed water quality purification system, preferably, the coverage area of the bio-carrier module in the water quality in-situ purification unit accounts for 10% -40% of the total area of the water to be purified.

In the above closed and semi-closed water quality purification system, preferably, the action area of water ecological restoration is 40-60% of the total area of the water to be purified.

The water quality purification method provided by the invention is formed by combining a plurality of treatment methods, the initial rainwater pretreatment reduces the pollution of initial rainwater to water quality, the sediment in-situ remediation realizes the remediation of the sediment of the water body to be purified (for example, the remediation of the sediment through a microorganism system), the water quality in-situ purification realizes the improvement of the water environment (for example, the improvement of the water environment is realized by combining artificial oxygenation, water system internal circulation and a biological carrier module), the water ecological remediation realizes the improvement of the water body biological diversity, nutrient elements in the water body are removed through the absorption of plant root systems, the algae is reduced through the animal filter feeding effect, organic pollutants in the sediment are reduced, the self-purification capacity of the water body is improved, and the self-purification of the water body is realized. The technical scheme provided by the invention improves the cooperative effect among the processing methods by adjusting the implementation time among the processing methods for the first time. Compared with the prior art, the technical scheme provided by the invention has the following advantages:

(1) the technical scheme provided by the invention can solve the problem of non-point source pollution caused by surface runoff of initial rainwater.

(2) According to the technical scheme provided by the invention, through the preliminary rainwater pretreatment, the bottom sediment in-situ remediation, and the water quality in-situ purification and the water ecological remediation which are mutually matched through a certain implementation sequence, the water body fluidity can be effectively improved, a water body ecological system is reconstructed, the biological diversity of the water body is enriched, the self-purification capacity of the water body is enhanced, organic pollutants, nitrogen, phosphorus and other nutrient elements in the water body are effectively absorbed, degraded and transferred, the water body transparency is improved, the water quality is in a stable state for a long time, and the problems of black and odor and eutrophication of the water body are prevented.

In a word, the technical scheme provided by the invention can be used for rapidly and excellently purifying the water quality of the water body, improving the self-purification capacity of the water body and recovering the ecological system of the water body by mutually matching the initial rainwater pretreatment, the bottom sediment in-situ remediation and the water quality in-situ purification and the water ecological remediation through a certain implementation sequence.

Drawings

FIG. 1 is a schematic flow chart of an embodiment of the present invention.

FIG. 2 is a schematic flow chart of an embodiment of the present invention.

FIG. 3 is a schematic flow chart of an embodiment of the present invention.

Detailed Description

The technical solutions of the present invention will be described in detail below in order to clearly understand the technical features, objects, and advantages of the present invention, but the present invention is not limited to the practical scope of the present invention.

In a specific embodiment 1 (as shown in fig. 1), the method for purifying the water quality of the closed and semi-closed water body comprises the steps of performing initial rainwater pretreatment, sediment in-situ remediation, water quality in-situ purification and water ecology remediation on the water body to be purified;

the initial rainwater pretreatment comprises the steps of utilizing an initial rainwater pretreatment unit to perform filler filtration, plant purification and microbial purification on rainwater entering a water body to be purified in advance, wherein the initial rainwater pretreatment unit is constructed around the coastwise of the water body to be purified and is communicated with the water body to be purified, and rainwater subjected to initial rainwater pretreatment can enter the water body; the initial rainwater pretreatment unit comprises plants, a filler layer and microorganisms, wherein the plants are planted on the upper layer of the filler layer, and the microorganisms are attached to the surface of the filler layer; wherein the packing layer is at least one of gravel, limestone, coal cinder, zeolite and the like; the plant is at least one of petiolus pulvinata, miscanthus floridulus, filipendula sikkmensis, pennisetum purpureum, pennisetum alopecuroides, Japanese black grass, and Carex aurantium;

the substrate sludge in-situ remediation adopts a microorganism remediation mode, wherein the microorganism is a heterotrophic microorganism, and the microorganism is selected from at least one of EM (effective microorganisms), photosynthetic bacteria, bacillus subtilis, nitrobacteria, denitrifying bacteria, saccharomycetes, lactic acid bacteria and the like;

the water quality in-situ purification adopts a mode of combining artificial oxygenation, water body internal circulation and a biological carrier module; wherein, the artificial oxygenation and the internal circulation of the water body adopt an intermittent operation mode, 5-8h is taken as an operation period, and the interval time is 1-3 h; the biological carrier module selects at least one of fibrous, strip-shaped and sheet-shaped fillers; artificial oxygenation and water internal circulation provide a favorable growing environment for the operation of the biological carrier module, aerobic microorganisms are attached to the biological carrier to grow to form a microbial film for purifying water quality, and a large number of microorganisms degrade pollutants in water through the metabolism effect to gradually purify the water quality; the equipment for realizing artificial oxygenation and internal circulation of the water body selects at least one of submersible aeration plug flow equipment, surface aeration equipment, fountain aeration equipment, pipeline aeration disturbance equipment and the like;

restoring the self-purification capacity of the water body by using submerged plants, emergent aquatic plants and aquatic animals in the water ecological restoration; wherein the submerged plant is selected from at least one of herba Swertiae Dilutae, black algae, Foliumet spicata, Goldfish algae and Potamogeton crispus, etc., and is planted in unit block or strip mode by planting 50-350 plants in unit square meter; the emergent aquatic plant is at least one of lotus, cattail, allium fistulosum, reed, calamus, phyllostachys praecox, loosestrife and the like, 10-20 plants are planted in a unit square meter, and the emergent aquatic plant planting area is a shallow water area close to the bank; the aquatic animals comprise a surface layer, a middle layer and a bottom layer, wherein the surface layer and the middle layer are selected from aquatic animals eating at least one of zooplankton, phytoplankton, humus and bacteria, and the bottom layer is selected from aquatic animals eating humus;

the area for implementing the in-situ remediation of the bottom mud accounts for 80-100% of the total area of the water body to be purified, the area for implementing the in-situ purification of the water quality accounts for 100% of the total area of the water body to be purified, and the area for implementing the ecological remediation of the water accounts for 40-60% of the total area of the water body to be purified;

firstly, rain pretreatment and water quality in-situ purification at the initial stage are synchronously carried out, then bottom sediment in-situ remediation is carried out, and finally water ecological remediation is carried out.

In another embodiment 2 (as shown in fig. 2), which is different from embodiment 1 only in the order of performing the initial rainwater pretreatment, the water quality in-situ purification, the sediment in-situ remediation, and the water ecology restoration, in this embodiment, the initial rainwater pretreatment and the sediment in-situ remediation are started at first, the water quality in-situ purification is started, and the water ecology restoration is started at last.

In another embodiment 3 (as shown in fig. 3), which is different from embodiment 1 only in the order of performing the preliminary rainwater pretreatment, the water quality in-situ purification, the sediment in-situ remediation, and the water ecology restoration, in this embodiment, the preliminary rainwater pretreatment is started at first, the water quality in-situ purification and the sediment in-situ remediation are started at the same time, and the water ecology restoration is started at last.

Example 1

The embodiment provides a method for purifying the water quality of closed and semi-closed water bodies

The method is used for purifying the water body of a landscape lake in a certain city, the area of the landscape lake is about 1 ten thousand square meters, the average depth of the lake water is about 1.0m, the lake body is more regular and elliptical, is positioned in a certain park in the city, and is an important water landscape in the park; because the water body of the landscape lake does not flow, visitors feed fishes in the lake with food, and a lot of pollutants are brought into the ground around the long-time atmospheric dust fall and rainfall erosion, the water body is blackened and smelled, the transparency of the water body is very low, the ecological system of the water body is damaged, and the pollutant content in bottom mud is also high due to the accumulation of the pollutants for a long time.

In order to recover the water quality and landscape effect of the landscape lake water body, the closed and semi-closed water body water quality purification method provided by the embodiment is adopted for water quality purification, and the specific steps are as follows:

1) preliminary rainwater pretreatment on water body to be purified

The circumference of the landscape lake (namely the water body to be purified) is about 400m, the initial rainwater treatment unit is arranged at the position 2m or so near the bank along the circumference, the arrangement depth of the initial rainwater treatment unit is about 0.5-1.5m, the width of the initial rainwater treatment unit is about 0.5-1m, the initial rainwater pretreatment unit is communicated with the water body to be purified, and rainwater pretreated by the initial rainwater can enter the water body; the initial rainwater pretreatment unit comprises plants, a planting soil layer, a packing layer and microorganisms, the packing layer comprises gravels, coal cinder and zeolite and adopts a layered laying mode that the particle size is gradually reduced from bottom to top, the packing layer is covered with the planting soil layer, the plants are planted in zones by selecting dwarf pampas grass, flowering awns and pinus gracilis, the plants are planted in the planting soil layer above the packing layer, the plants take roots and grow to absorb nutrient elements in the initial rainwater and are filtered by the packing layer, and the microorganisms are attached to the surface of the packing layer to perform biological evolution on the rainwater;

in a word, the initial rainwater pretreatment unit is used for performing filler filtration, plant purification and microbial purification on rainwater entering a water body to be purified in advance to realize initial rainwater pretreatment on the water body to be purified; the pretreated rainwater flows into the water body to be purified through a pipeline to serve as a normal water replenishing source, the initial rainwater pretreatment improves the water quality purification effect, and meanwhile, the surrounding landscape environment is improved;

2) performing initial rainwater pretreatment on a water body to be purified and simultaneously performing in-situ purification on water quality

The water quality in-situ purification adopts a mode of combining artificial oxygenation, internal circulation of a water body and a biological carrier module to promote water quality purification, improve the dissolved oxygen environment of the water body to be purified and improve the water body fluidity; the artificial oxygenation and the internal circulation of the water body adopt a continuous operation mode at the initial implementation stage of water quality purification, when the dissolved oxygen reaches more than 2mg/L, the intermittent operation mode is adopted, and 5 hours are taken as an operation period and the interval time is 2 hours; meanwhile, the fountain aeration improves the landscape effect of the water body; the biological carrier module comprises 50 groups of biological carriers, each group of biological carriers adopts a mode of combining fibrous and flaky fillers, and each group of modules is provided with 10 bundles of fibrous carriers and 10 sheets of flaky carriers. 50 groups of biological carriers are uniformly distributed in the water body to be purified; the artificial oxygenation and water internal circulation provide a favorable growth environment for the operation of the biological carrier module, so that aerobic microorganisms are attached to the biological carrier to grow to form a microbial film for purifying water quality, and a large amount of microorganisms degrade pollutants in water through the metabolism effect to gradually realize the purification of the water quality;

after the water quality is purified in situ, the water quality of the water body to be purified is gradually improved, the transparency is obviously improved, the dissolved oxygen is more than 2mg/L, and the dead water circularly flows, so that the degradation of the pollutants in the water body by microorganisms is promoted, and the black and odorous problem of the water body is improved;

3) 3 days after the initial rainwater pretreatment and the water quality in-situ purification are implemented, performing in-situ remediation on the sediment

Bottom sediment in-situ remediation is implemented by adopting a bottom sediment remediation agent containing a plurality of beneficial microorganisms, and the coverage area of the bottom sediment in-situ remediation is 8000 square meters; specifically, the sediment repairing agent is uniformly scattered into the water body to be purified, and organic pollutants in the sediment are degraded under the metabolism of microorganisms, so that the original black and odorous sediment is inorganized and turns into earthy yellow, the pollution to the overlying water body is reduced, and the sediment environment is more suitable for the growth of aquatic plants to realize the in-situ repair of the sediment; wherein the bottom sediment repairing agent contains EM bacteria, photosynthetic bacteria, bacillus subtilis, nitrobacteria, denitrifying bacteria, lactic acid bacteria and the like.

4) Finally, performing water ecological restoration

The initial rainwater pretreatment, the water quality in-situ purification and the sediment in-situ remediation are implemented, the water quality is gradually improved after about 15 days after the sediment in-situ remediation is implemented, the water transparency is obviously improved, the bottom of the water body is illuminated, the construction of an aquatic ecosystem can be met, and then the aquatic ecosystem is repaired;

restoring the self-purification capacity of the water body by using submerged plants, emergent aquatic plants and aquatic animals in the water ecological restoration; the submerged plant is planted by selecting two kinds of eel grass and eel algae, the water body to be purified is evenly divided into five areas for planting, equipment for realizing artificial oxygenation and internal circulation of the water body and a biological carrier module are avoided during planting, the coverage area of the submerged plant is about 6000 square meters, the coverage area of the eel grass is about 4500 square meters, the planting density is about 50 plants/square meter, the coverage area of the eel algae is about 1500 square meters, and the planting density is about 30 plants/square meter; emergent aquatic plants are planted in a shallow water area with the water depth of about 0.5m within 2m close to the bank of the water body to be purified, the emergent aquatic plants can be decorated as a landscape and have a certain purification effect on water quality, and after 10 days of planting, the plants grow well, wherein the coverage area of the yellow calamus is about 50 square meters, the planting density is 20-25 clusters/square meter, each cluster is about 2-3 buds, the coverage area of the loosestrife is about 60 square meters, the planting density is about 16-25 clusters/square meter, the coverage area of the arundo donax linn is about 50 square meters, the planting density is 6-10 clusters/square meter, and each cluster is 5-8 buds; after the plants grow stably, putting aquatic animals, and putting 100 fish fries of silver carps, 30 fish fries of bighead carps, 40kg of benthonic mussels, 25kg of snails and 5kg of shrimps into the water body to be purified;

a good water body ecological system is constructed, so that the good ecological system consisting of animals, plants and microorganisms is formed in water, the water environment is gradually improved, the self-purification capacity of the water body is improved, and the water quality is improved.

The synchronous implementation of the initial rainwater pretreatment and the water quality in-situ purification can shorten the construction period on one hand, and the synchronous implementation of the initial rainwater pretreatment and the water quality in-situ purification can improve the water quality in advance before the implementation of the sediment in-situ remediation and the water ecology remediation on the other hand, so that good basic conditions are provided for the subsequent sediment in-situ remediation and the water ecology remediation.

The landscape lake adopts the closed and semi-closed water quality purification method provided by the embodiment to purify the water, the transparency of the water is more than 1m about 30 days after the implementation of the water ecological restoration, and the treatment effect of clearness and bottoming is achieved. The dissolved oxygen keeps the level more than 2.5mg/L, COD, BOD5, ammonia nitrogen and total phosphorus reach the standard of surface water IV, the submerged plant grows well, the landscape effect of the underwater green lawn is formed, the surrounding landscape of the water body is improved, the water quality purification system operates stably, and the water ecological system keeps stable.

The embodiment also provides a closed and semi-closed water quality purification system, wherein, this system includes: the system comprises a rainwater pretreatment unit constructed in the embodiment when the initial rainwater pretreatment is carried out on the water body to be purified, a water quality in-situ purification unit constructed in the embodiment when the water body to be purified is subjected to water quality in-situ purification treatment, a sediment in-situ remediation unit constructed in the embodiment when the water body to be purified is subjected to sediment in-situ remediation, and a water ecology remediation unit constructed in the embodiment when the water body to be purified is subjected to water ecology remediation;

arranging an initial rainwater treatment unit along the circumference at a position 2m or so near the bank of the water body to be purified, wherein the depth of the initial rainwater treatment unit is about 0.5-1.5m, the width of the initial rainwater treatment unit is about 0.5-1m, the initial rainwater pretreatment unit is communicated with the water body to be purified, and rainwater pretreated by the initial rainwater can enter the water body; the initial rainwater pretreatment unit comprises plants, a planting soil layer, a packing layer and microorganisms, the packing layer comprises gravels, coal cinder and zeolite and adopts a layered laying mode that the particle size is gradually reduced from bottom to top, the packing layer is covered with the planting soil layer, the plants are planted in zones by selecting dwarf pampas grass, florists and stipa capillata, the plants are planted in the planting soil layer above the packing layer, the plants take roots and grow to absorb nutrient elements in the initial rainwater and are filtered by the packing layer, the microorganisms are attached to the surface of a substrate of the packing layer to carry out biological evolution on the rainwater, and the microorganisms comprise facultative bacteria, anaerobic bacteria and aerobic bacteria;

the water quality in-situ purification unit comprises a device for realizing artificial oxygenation and internal circulation of the water body to be purified and a biological carrier module, aerobic microorganisms are attached to and grow on the biological carrier, and the device for realizing artificial oxygenation and internal circulation of the water body to be purified provides a favorable growth environment for the operation of the biological carrier module; the device for realizing the artificial oxygenation and internal circulation of the water body to be purified is a submersible aeration plug flow device and a fountain aeration device, and specifically 2 submersible aeration plug flow devices and 2 fountain aeration devices are arranged in the water body to be purified; the biological carrier module comprises 50 groups of biological carriers, each group of biological carriers adopts a mode of combining fibrous and flaky fillers, and the 50 groups of biological carriers are uniformly distributed in the water body to be purified;

the bottom sediment in-situ remediation unit is used for performing bottom sediment remediation on the water body to be purified through microorganisms, and the coverage area of the bottom sediment in-situ remediation unit is about 8000 square meters;

the water ecological restoration unit comprises a submerged plant group, an emergent aquatic plant group and an aquatic animal group; the submerged plant group comprises two types of eel grass and eel algae, the planting is carried out through a fork planting method, the water body to be purified is evenly divided into five areas for planting, equipment for realizing artificial oxygenation and internal circulation of the water body and a biological carrier module are avoided during planting, the coverage area of the submerged plants is about 6000 square meters, the coverage area of the eel grass is about 4500 square meters, the planting density is about 50 plants per square meter, the coverage area of the eel algae is about 1500 square meters, and the planting density is about 30 plants per square meter; planting emergent aquatic plant groups in a shallow water area (within 2m range close to the bank and with the water depth of about 0.5m) of a water body to be purified close to the bank, wherein the coverage area of calamus is about 50 square meters, the planting density is 20-25 clusters/square meter, each cluster is about 2-3 buds, the coverage area of loosestrife is about 60 square meters, the planting density is about 16-25 clusters/square meter, the coverage area of arundo donax is about 50 square meters, the planting density is 6-10 clusters/square meter, and each cluster is 5-8 buds; the aquatic animal group comprises 100 chub fries, 30 bighead carp fries, 40kg of benthonic mussels, 25kg of snails and 5kg of shrimps.

Example 2:

The method is used for purifying a city landscape river channel, the total length of the river channel is about 2km, the width of the river channel is about 20m, the total area is about 4 ten thousand square meters, the average water depth is 2m, the river channel is semi-closed, the water body is in a relative static state in other time except for obvious water flow in rainy season due to poor water body fluidity, and the water body is in a dead water state, in addition, surface runoff pollution and few steal discharge of coastal residents in rainy season cause water body water quality deterioration, the water body transparency is about 0.5m, the water body is turbid and has peculiar smell, the living environment of the surrounding residents is damaged, and adverse effects are caused on city appearance.

In order to purify the water quality of the water body and improve the current situation of the water environment, the method is matched with a local administrative department, firstly, the problem of steal discharge of residents along the shore is treated, the steal discharge pipeline enters a municipal pipe network system through sewage interception and is treated in a unified way, and then, the method for purifying the water quality of the closed and semi-closed water body provided by the embodiment is adopted to purify the water quality, and the method specifically comprises the following steps:

1) preliminary rainwater pretreatment on water body to be purified

The whole length of the polluted river channel (namely the water body to be purified) is 2km, initial rainwater treatment units are arranged at about 4m close to the bank along two banks of the river channel, the depth of each unit is about 1.0m, the width of each unit is about 1.0m, the initial rainwater pretreatment units are communicated with the water body to be purified, and rainwater pretreated by the initial rainwater can enter the water body; the initial stage rainwater preliminary treatment unit includes plant, planting soil layer, packing layer and microorganism, and initial stage rainwater preliminary treatment unit packing layer comprises the gravel, and the particle diameter range is about 4 ~ 50mm, and the gravel particle diameter reduces gradually from bottom to top, and the planting soil layer is laid to the top, plants at planting soil layer, and the plant species selects short pampas grass, thin leaf needle mango, canna etc. plants the view of interspecific planting in the segmentation. The plant root system of the initial rainwater pretreatment unit absorbs total pollutants of initial rainwater, the packing layer and microorganisms on the root system degrade the pollutants, and the packing layer filters the pollutants in the water body.

2) Carrying out in-situ remediation on bottom mud while carrying out initial rainwater pretreatment on a water body to be purified

The water body to be purified is in an urban area, the dredging is difficult, the influence is large, the sediment is repaired in a sediment in-situ repairing mode, and the influence on the surrounding environment is reduced. The in-situ range of the bottom mud is the whole water body to be purified, and the coverage area is about 40000 square meters; specifically, the bottom sediment in-situ restoration agent is uniformly scattered in a water body through manual scattering of a ship, organic pollutants in the bottom sediment are degraded by utilizing the degradation effect of microorganisms such as EM (effective microorganisms), photosynthetic bacteria, nitrobacteria and denitrifying bacteria in the bottom sediment in-situ restoration agent, nitrogen in the bottom sediment is removed, the bottom sediment is gradually purified, and the bottom sediment environment is improved.

3) After the initial rainwater and bottom mud are restored in situ for 5 days, the water body is purified in situ

The water quality in-situ purification adopts a mode of combining artificial oxygenation, internal circulation of a water body and a biological carrier module to promote water quality purification, improve the dissolved oxygen environment of the water body to be purified and improve the water body fluidity; the artificial oxygenation and water internal circulation adopt a mode of combining submersible aeration plug flow equipment and pipeline aeration equipment, wherein the submersible aeration plug flow equipment accounts for 10, the pipeline aeration equipment accounts for 5, the pipeline aeration equipment is arranged at the middle position of a river channel, the submersible aeration plug flow equipment is arranged at the interval of about 100m, two pipeline aeration equipment are continuously arranged, a set of pipeline aeration equipment is arranged at the interval of about 100m, the coverage range is about 200m, 5 units are repeatedly arranged in the middle of the river channel as one unit, the system is operated in an intermittent aeration mode, 6 hours are taken as an operation period, the interval time is 3 hours, dissolved oxygen is supplemented to the water, the water body fluidity is increased, and the water body dead water state is improved; the biological carrier module selects a mode of combining a strip-shaped biological carrier with a flaky filler, wherein 5 strip-shaped biological carriers are in one group, the total number is 1000, the flaky carriers are in 200 groups of flaky fillers, 10 sheets of each group provide a place for the attachment growth of microorganisms in the water body, a biological film is formed on the surface of the filler, and the pollutants in the water body are degraded through the metabolism of the microorganisms, so that the water quality is improved.

4) Finally, performing water ecological restoration

After the water quality is purified in situ, water ecological restoration is started when the water quality is gradually improved, the transparency of the water body is improved, the dissolved oxygen is more than 2mg/L and the water bottom is irradiated by light;

the water ecological restoration system restores the water body which loses ecological balance by using submerged plants and aquatic animals, and improves the self-purification capacity of the water body. The submerged plants are combined by selecting dwarf tape grass, elodea nutgrass and hydrilla verticillata, the plants are planted in different regions by adopting a fork planting method, wherein the coverage area of the dwarf tape grass is about 7000 square meters, the planting density is about 40 plants/square meter, the elodea nutgrass is 4000 square meter, the planting density is about 20 plants/square meter, the hydrilla verticillata is 5000 square meters, the planting density is about 30 plants/square meter, the planting is carried out in a region strip type mode, and equipment and a biological carrier module for realizing artificial oxygenation and water body internal circulation are avoided during planting; the growth of the submerged plants absorbs nutrient elements in the water body, the water quality of the water body is improved, and after the water quality is gradually improved and the submerged plants grow stably, aquatic animals are thrown, wherein 350 fries of silver carps, 120 fries of bighead carps, 150kg of mussels of benthonic animals, 100kg of snails and 25kg of shrimps are thrown into the submerged plants. Utilize the zoobenthos to the absorption effect of pollutant in bottom water and the bed mud, purify water and bed mud, improve water quality, finally realize the structure of the complete ecosystem of water, finally get rid of the pollutant from the water through the mode that the plant was reaped, the animal was salvaged, realize water purification, resume water ecosystem, improve water self-purification ability.

The method for purifying the water quality of the closed and semi-closed water body provided by the embodiment is used for purifying the water body, the transparency of the water body is improved to 1.5m after the implementation of the ecological restoration of the water body for 25 days, plants in the water grow well, aquatic animals grow stably, the dissolved oxygen level in the water body is kept above 2mg/L, the original black and odorous problem of the water body to be purified is eliminated, the living environment of surrounding residents is improved, and the whole system runs stably.

arranging initial rainwater treatment units along two banks of the water body to be purified at the position 4m or so close to the bank edge of the water body to be purified, wherein the depth of the initial rainwater treatment units is about 1m, the width of the initial rainwater treatment units is about 1m, the initial rainwater pretreatment units are communicated with the water body to be purified, and rainwater subjected to initial rainwater pretreatment can enter the water body; the initial rainwater pretreatment unit comprises plants, a planting soil layer, a packing layer and microorganisms, wherein the packing layer is composed of gravels, the particle size range is about 4-50 mm, the particle size of the gravels is gradually reduced from bottom to top, the planting soil layer is covered on the packing layer, the plants are selected from dwarf pampas grass, thin-leaf needle awns and canna indica and are planted in sections, the plants are planted in the planting soil layer above the packing layer, the plants take roots and grow to absorb nutrient elements in the initial rainwater and are filtered by the packing layer, the microorganisms are attached to the surface of a substrate of the packing layer and plant roots to biologically evolve the rainwater, and the microorganisms comprise facultative bacteria, anaerobic bacteria and aerobic bacteria;

the water quality in-situ purification unit comprises a device for realizing artificial oxygenation and internal circulation of the water body to be purified and a biological carrier module, microorganisms are attached to and grow on the biological carrier, and the device for realizing artificial oxygenation and internal circulation of the water body to be purified provides a favorable growth environment for the operation of the biological carrier module; the device for realizing the artificial oxygenation of the water body to be purified and the internal circulation of the water body is a submersible aeration plug flow device and a pipeline aeration device, particularly the submersible aeration plug flow device comprises 10 submersible aeration plug flow devices, 5 pipeline aeration devices are arranged at the middle position of a river channel, one submersible aeration plug flow device is arranged at the interval of about 100m, two pipeline aeration devices are continuously arranged, a set of pipeline aeration device is arranged at the interval of about 100m, the coverage range is about 200m, and 5 units are repeatedly arranged in the middle of the river channel by taking the pipeline aeration devices as one unit; the biological carrier module selects a mode of combining strip-shaped and sheet-shaped fillers, wherein 5 strip-shaped biological carriers form one group, the total number is 1000 groups, the sheet-shaped carriers form 200 groups of sheet-shaped fillers, each group comprises 10 sheets, and the biological carriers are uniformly distributed in the water body to be purified;

the sediment in-situ remediation unit is used for performing sediment remediation on the water body to be purified through microorganisms, and the coverage area of the sediment in-situ remediation unit is about 40000 square meters;

the water ecological restoration unit comprises a submerged plant group and an aquatic animal group; the submerged plant group comprises dwarf eel grass, elodea nuttallii and hydrilla verticillata, and is planted by a fork planting method, and equipment and a biological carrier module for realizing artificial oxygenation and internal circulation of a water body are avoided during planting, wherein the coverage area of the dwarf eel grass is about 7000 square meters, the planting density is about 40 plants/square meter, the elodea nuttallii is 4000 square meters, the planting density is about 20 plants/square meter, the hydrilla verticillata is 5000 square meters, the planting density is about 30 plants/square meter, and strip partition type planting is adopted; the aquatic animal group comprises 350-fish fries of silver carps, 120-fish fries of bighead carps, 150kg of benthonic mussels, 100kg of snails and 25kg of shrimps.

Example 3:

The method is used for purifying a landscape pit in a certain rural area, the pit is located in a certain village, the area is about 2000 square meters, the average water depth is 1.5m, the pit is modified for improving the overall environment of the village and the appearance of the village, the aim is to enable the pit to become the landscape pit in the village, but at present, the pit is polluted by surrounding domestic garbage for a long time and sewage poured by surrounding villages, so that the water quality of a water body is blackened and smelly, the transparency of the water body is almost zero, and the pit becomes a smelly water pit.

In order to purify the water quality of the water body in the landscape pool, firstly, garbage around the pool is cleaned, and residents around the pool are prohibited to pour domestic sewage into the pool, then the closed and semi-closed water quality purification method provided by the embodiment is adopted to purify the water quality, and the ecological system of the pool is recovered, so that the pool becomes a landscape pool of a village and a small town. The method comprises the following specific steps:

1) preliminary rainwater pretreatment

The circumference of the landscape pond (namely the water body to be purified) is about 200m, an initial rainwater treatment unit is arranged at the position 4m or so close to the edge of the pond along the circumference of the pond, the setting depth of the initial rainwater treatment unit is about 1m, the width of the initial rainwater treatment unit is about 1m, and the initial rainwater treatment unit is connected with the water body to be treated through a pipeline, so that the treated initial rainwater enters the water body to be purified through the pipeline to be used as ecological water supplement of the water body to be purified; the initial rainwater pretreatment unit comprises plants, a planting soil layer, a packing layer and microorganisms, wherein the plants are planted on the planting soil layer above the packing layer in a partition zone, the packing layer is combined by gravel and cinder, the grain diameter is gradually reduced from bottom to top, the plants are laid in a layered mode, the planting soil layer is covered above the packing layer to plant the plants, the re-planting area is about 100 square meters, the planting density is 2 per square meter, 10 buds per cluster, the short pampas grass is about 100 square meters, and the planting density is about 20 plants per square meter. The plants root in the planting soil, primary rainwater is primarily purified through the absorption of the root systems and microorganisms attached to the root systems and the filler layer, pollutants are further filtered through the filter layer, the purified water is discharged into the water body to be purified through the pipeline, the quality of the primary rainwater entering the water body to be purified is improved, and the pollution amount brought by the primary rainwater is reduced; meanwhile, the planted plants play a role in creating landscapes for the surrounding environment.

2) After the initial rainwater pretreatment normally runs, simultaneously carrying out sediment in-situ remediation and water quality in-situ purification on the water body to be purified

The bed mud normal position is restoreed and is adopted the bed mud normal position restoration microbial inoculum that contains EM fungus, nitrobacteria, denitrifying bacteria, photosynthetic bacteria to restore, through the artifical mode of throwing to spill, evenly throw and spill in treating the purification water, the prosthetic coverage area of bed mud normal position is 2000 square meters, after bed mud normal position restoration microbial inoculum entered into the bed mud, through the metabolism of microorganism, degrade the pollutant in the bed mud gradually, make most top layer bed mud be degraded into inorganic matter gradually, reduce the secondary pollution to overlying water, improve the bed mud habitat.

In the in-situ remediation process of the sediment, water quality in-situ purification is simultaneously implemented, the water quality purification is promoted by adopting a mode of combining artificial oxygenation, water body internal circulation and a biological carrier module, the water body dissolved oxygen environment of the water body to be purified is improved, and the water body fluidity is improved; wherein, the artificial oxygenation and the internal circulation of the water body are carried out by using submersible aeration plug flow aeration equipment and fountain aeration equipment, and 2 submersible aeration plug flow aeration equipment and 1 fountain aeration equipment are arranged in the water body to be purified; 2, the submersible aeration plug flow aeration equipment is arranged in pairs under water, so that the water body forms an internally circulating flowing body and dissolved oxygen is uniformly diffused to each corner of the water body; 1, the fountain is arranged in the middle of the water body to be purified in an aeration way, so that the landscape effect of the water body to be purified is improved while the water body is aerated; the biological carrier modules are 40 groups of block modules, and each group of five blocks is uniformly placed in the water tank to provide a place for attachment growth of microorganisms existing in the water body, so that a large amount of microorganisms are attached to form a biological film, and pollutants in the water body are degraded;

after in-situ remediation of the bottom mud and in-situ purification of the water quality are carried out, the water body finally realizes the circulating flow, and the dissolved oxygen level of the water body reaches more than 2.0 mg/L; improving the water quality of the water body and solving the problem of black and stink water body.

3) Finally, performing water ecological restoration

After the sediment in-situ remediation and the water quality in-situ purification are implemented, the water quality of the water body is gradually improved, the black and odorous problem of the water body is obviously improved after 7 days, the transparency is gradually improved, the bottom of the water body is irradiated after 20 days, the system runs stably, the biofilm formation of the biological carrier is complete, and at the moment, the water ecological remediation is carried out on the water body;

the water ecological restoration adopts a submerged plant planting and aquatic animal throwing mode to restore the damaged water ecological system and restore the self-purification capacity of the water body; wherein, the submerged plant is selected from dwarf tape grass, the coverage area is about 1400 square meters, the total area of the water body is 70 percent, the submerged plant is divided into 4 blocks for planting, and the equipment for realizing artificial oxygenation and internal circulation of the water body and a biological carrier module are avoided during planting; after submerged plants are planted, nutrient elements such as nitrogen and phosphorus in a water body are taken as main nutrient sources through photosynthesis, absorption and utilization are carried out, the submerged plants grow gradually, after 30 days, the root system is stable, aquatic animals begin to be thrown into the water body, the food chain of a water ecological system is perfected, the aquatic animals select silver carps and bighead carps as main fish species, mussels, snails and shrimps as main benthonic animals, wherein the number of the thrown silver carps is 30, the number of the thrown bighead carps is 10, the number of the thrown mussels is 10, the number of the mussels is 5kg and the number of the shrimps is 2 kg;

the method comprises the steps of constructing a complete food chain system in the water body to form a complete water ecosystem, absorbing and degrading pollutants in the water body through the combined action of animals, plants and microorganisms, improving the self-purification capacity of the water body, and finally removing the pollutants from the water body through the mode of salvaging the animals and the plants to form a complete purification system.

The pit and pond landscape water body is purified by adopting the closed and semi-closed water body water quality purification method provided by the embodiment, the transparency of the water body is more than 1.5m after about 60 days from the implementation of water ecological restoration, and the clear and thorough treatment effect is achieved. The dissolved oxygen keeps the level more than 2.5mg/L, COD, BOD5, ammonia nitrogen and total phosphorus reach the standard of surface water IV, the submerged plant grows well, the landscape effect of the underwater green lawn is formed, the surrounding landscape of the water body is improved, the water quality purification system operates stably, and the water ecological system keeps stable.

arranging an initial rainwater treatment unit along the circumference at a position 4m or so near the bank edge of a water body to be purified, wherein the depth of the initial rainwater treatment unit is about 1m, the width of the initial rainwater treatment unit is about 1m, the initial rainwater pretreatment unit is communicated with the water body to be purified, and rainwater subjected to initial rainwater pretreatment can enter the water body; the initial rainwater pretreatment unit comprises plants, a planting soil layer, a packing layer and microorganisms, the packing layer comprises gravels and coal cinder and adopts a layered laying mode that the particle size is gradually reduced from bottom to top, the packing layer is covered with the planting soil layer, the plants select re-flowering flowers and dwarf pamplegrass and are planted in zones, the plants are planted in the planting soil layer above the packing layer, the plants take roots and grow to absorb nutrient elements in the initial rainwater and are filtered by the packing layer, the microorganisms are attached to the surface of a substrate of the packing layer and plant roots to carry out biological evolution on the rainwater, and the microorganisms comprise facultative bacteria, anaerobic bacteria and aerobic bacteria;

the water quality in-situ purification unit comprises a device for realizing artificial oxygenation and internal circulation of the water body to be purified and a biological carrier module, aerobic microorganisms are attached to and grow on the biological carrier, and the device for realizing artificial oxygenation and internal circulation of the water body to be purified provides a favorable growth environment for the operation of the biological carrier module; the device for realizing the artificial oxygenation and internal circulation of the water body to be purified is a submersible aeration plug flow device and a fountain aeration device, specifically 2 submersible aeration plug flow devices are arranged in the water body to be purified in a diagonal manner, and 1 fountain aeration device is arranged in the center of the water body to be purified; the biological carrier module comprises 40 groups of biological carriers, each group of biological carriers adopts blocky fillers, and the 40 groups of biological carriers are uniformly distributed in the water body to be purified;

the sediment in-situ remediation unit is used for performing sediment remediation on the water body to be purified through microorganisms, and the coverage area of the sediment in-situ remediation unit is about 2000 square meters;

the water ecological restoration unit comprises a submerged plant group and an aquatic animal group; the submerged plant group is selected from dwarf tape grass, the cover area is about 1400 square meters, the total area of the water body is 70 percent, the submerged plant group is divided into 4 blocks for planting, and equipment for realizing artificial oxygenation and internal circulation of the water body and a biological carrier module are avoided during planting; the aquatic animal group comprises 30 silver carp fries, 10 bighead carp fries, 10kg of benthonic mussels, 5kg of snails and 2kg of shrimps.

Claims

1. A closed and semi-closed water body water quality purification method, said method comprises treating the water body to be purified with preliminary rainwater, the original position of bottom mud is repaired, water quality original position purifies and water ecological remediation; wherein, the initial rainwater pretreatment, the sediment in-situ remediation and the water quality in-situ purification are all carried out before the water ecological remediation is carried out.

2. A water purification method according to claim 1, wherein the initial rainwater treatment is started at a time not later than the time at which the sediment in-situ remediation and the water quality in-situ purification are started.

3. A water purification method according to claim 2, wherein the initial rainwater pretreatment, the sediment in-situ remediation, the water in-situ purification and the water ecology remediation are performed in the following order:

the method comprises the following steps of firstly, implementing rain pretreatment in an initial stage, then synchronously implementing water quality in-situ purification and sediment in-situ remediation, and finally implementing water ecological remediation; or

Firstly, synchronously implementing initial rainwater pretreatment and water quality in-situ purification, then implementing bottom sediment in-situ remediation, and finally implementing water ecological remediation; or

Firstly, synchronously implementing initial rainwater pretreatment and sediment in-situ remediation, then implementing water quality in-situ purification, and finally implementing water ecological remediation.

4. A water purification method according to claim 1,

the initial rainwater pretreatment comprises the steps of utilizing an initial rainwater pretreatment unit to perform filler filtration, plant purification and microbial purification on rainwater entering a water body to be purified in advance, wherein the initial rainwater pretreatment unit is constructed around the coastwise of the water body to be purified and is communicated with the water body to be purified, and rainwater subjected to initial rainwater pretreatment can enter the water body;

the in-situ remediation of the sediment adopts a microorganism remediation mode, wherein the microorganism is a heterotrophic microorganism;

the water quality in-situ purification adopts a mode of combining artificial oxygenation, water body internal circulation and a biological carrier module to promote the water quality purification;

the water ecological restoration uses at least one of submerged plants, emergent aquatic plants and aquatic animals to restore the self-purification capacity of the water body.

5. The water purifying method according to claim 4, wherein the initial rainwater pretreatment unit comprises plants, a planting soil layer, a packing layer and microorganisms, wherein the packing layer is arranged at the lower part of the planting soil layer, the plants are planted in the planting soil layer above the packing layer, the microorganisms are attached to the root systems of the plants, soil particles in the planting soil layer and/or the surface of the packing layer, and the microorganisms comprise at least one of facultative bacteria, anaerobic bacteria and aerobic bacteria.

6. A water purification method according to claim 5,

the filling material layer in the initial rainwater pretreatment unit selects at least one of gravel, limestone, coal cinder and zeolite;

the plants in the initial rainwater pretreatment unit are at least one of petasites japonicus, miscanthus floridulus, stipa capillata, pennisetum purpureum, pennisetum alopecuroides, hemsleya japonica and Carex aurantifolia.

7. A water purification method as claimed in claim 4, wherein the microorganisms used for in situ remediation of the sediment comprise at least one of EM bacteria, photosynthetic bacteria, Bacillus subtilis, nitrifying bacteria, denitrifying bacteria, yeast and lactic acid bacteria.

8. A water purification method according to claim 4,

the artificial oxygenation and the internal circulation of the water body adopt an intermittent operation mode;

the bio-carrier module includes at least one of fibrous, strip-shaped, and sheet-shaped packing.

9. A water purification method according to claim 4 or 8, wherein the artificial oxygen aeration and internal circulation device comprises at least one of a submersible aeration plug flow device, a surface aeration device, a fountain aeration device and a pipeline aeration disturbance device.

10. A water purification method according to claim 4,

the submerged plant comprises at least one of herba Picrasmae, black algae, Foliumet spicatum, Goldfish algae and Potamogeton crispus;

the emergent aquatic plant comprises at least one of flos Nelumbinis, rhizoma Typhae, herba Alii Fistulosi, rhizoma Phragmitis, rhizoma Acori Calami, Ecliptae herba and herba Lydrobii;

the aquatic animals comprise surface layer, middle layer and bottom layer, wherein the surface layer and middle layer are selected from aquatic animals feeding on at least one of zooplankton, phytoplankton, humus and bacteria, and the bottom layer is selected from aquatic animals feeding on humus.

11. The water purifying method according to claim 10,

planting 50-350 plants in unit square meter of submerged plant;

the planting density of emergent aquatic plants is 10-20 plants planted in unit square meter, the distance between the planting area of the emergent aquatic plants and the bank side is not more than 5m, and the water depth of the planting area of the emergent aquatic plants is not more than 0.5 m.

12. A water purification method according to claim 4,

the area for implementing the in-situ remediation of the bottom mud is 80-100% of the total area of the water body to be purified;

the acting area of artificial oxygenation and internal circulation of the water body in the implementation of water quality in-situ purification is 100 percent of the total area of the water body to be purified;

the coverage area of the biological carrier module accounts for 10 to 40 percent of the total area of the water body to be purified in the implementation of the water quality in-situ purification;

the area for implementing the water ecological restoration accounts for 40 to 60 percent of the total area of the water body to be purified.

13. A closed and semi-closed water quality purification system for realizing the closed and semi-closed water quality purification method of any one of claims 1 to 12, wherein the system comprises: the system comprises an initial rainwater pretreatment unit, a sediment in-situ remediation unit, a water quality in-situ purification unit and a water ecological remediation unit; wherein the content of the first and second substances,